It is often desirable to provide a cover the truck bed of a pickup truck for shielding the contents of the truck bed from wind, rain, and the like. Because it could desirable to cover only a portion of the truck bed when requiring an uncovered portion for carrying items that are too large to fit beneath the truck bed cover, it would be a benefit to have a truck bed cover that was variably extendable to cover a user selected portion of the truck bed.